jbl-1985

So my 2000 ES threw these codes last week, and I checked the gas cap, all of the hoses, etc., and everything seems in order. Gas cap passed integrity test at an ADOT smog testing station, so that is not an issue.

Funny story, I was IN LINE to get my car smog tested and the CEL came on right then...backed out and came home and used my scan tool to clear the codes, went back and passed the test...

Anyway, I read up on what could be causing this and the charcoal canister came up, and many people have said that this unit will last 10x longer than the car. I checked the hoses going to the canister and again they all look intact and connected. Another opinion is that you shouldn't top off your tank, and this I am guilty of. I mean, I top it off until you can't put any more gas in the tank...The thought is some gas may have made it's way into the canister, but when it has had a chance to dry out, the CEL will go out.

Thoughts on this everyone? I reset the CEL about 250 miles ago and it has not come back on.

JetsonES

Have you removed the plastic engine cover and checked the mess of hoses and vsvs under there? The cover hides a lot and you may have something broken or off a barb under there.

jbl-1985

Sure did. Everything under the engine cover is in tact as well.

808mcv20l

running into this issue on my sister's 98 camry 1mz.

Here's all the things that we've done so far.

Her car was exhibiting surges and low idle after slowing to a stop from coming off a freeway.

That issue was resolved when I replaced the EGR valve itself and cleaned the tube.

However, the P0446 still comes up after a CEL clear via obd2 bluetooth dongle in a few days or week.

I've already replaced 2 of the 3 VSV valves under the plastic cover to no avail. (those Electrical connectors are super brittle and the holding tabs break from the heat. I've already replaced them as they've broke.

checked the hoses and they all seem to be ok.

I'm almost convinced it's the charcoal canister itself that's causing this issue.

The other thing is my sister tops off her gas which doesn't help the issue.

If you find a solution I'd be happy to hear it.


If I were you I'd start by trying to clean out that EGR valve.

you can also test the VSVs by putting a 9volt battery to the pins, they should click.

jbl-1985

Not experiencing any surge like your sis's Camry, just the codes that came up. As I mentioned all of the hoses look good, but I haven't checked the VSV valves specifically. I am assuming they are under the plastic engine cover. I'll look today and post if anything looks awry. I looked under the engine cover already and everything was in tact.

For now I am sitting tight and in theory letting the charcoal canister dry out...I top off to the extreme but have done so for years...On all of my cars. So why would I just start getting these codes now is the question I would have. I will keep you posted on any developments.

You have the same car as I do - I have the Platinum edition only with a few more miles

mmatheny

Double check the hose BEHIND the filter box. I got the same codes and reattaching it fixed then. Whodathunk that hose actually DID something??

jbl-1985

I'm assuming you mean the air filter box. There is a small device attached to the back of the box, and all electrical and evap hoses are accounted for.

NotADood

Lexus Master tech here.

Usual causes for the three codes you listed above in usual order...

cracked evap purge hose
stuck open purge VSV (vacuum switching valve)
and finally if all else fails, stuck open CSV (canister switching valve) resulting in charcoal canister replacement.

JetsonES

Very cool, thanks for the breakdown NotADood.

jbl-1985

Thanks much for the info. Can I ask were in the engine bay (or otherwise) would be the evap purge hose is located and 2), which VSV valve needs to be checked - all of them? There are two from what I can tell under the Engine cover.

Thanks again.

funcrusher

These same 3 codes popped up on my 2000 es after the Check Engine and Trac Off lights came on today. Ran to Autozone and had it scanned right after. Weird because i just replaced 2 oil control valves from other codes last week.

I found this from the same codes on a RX thread "These are the 3 codes you get when the evap hose is disconnected behind the air filter box."

So about to check on everything before i spend money!

jbl-1985

At the end of the day, I had to replace the canister. You can get them online cheaper than the dealer will charge.

80es300

Keep us posted if that fixed your problem? I had these codes for sometime on & off and also could smell gas sometimes. I was speculating the canister but my mechanic changed a VSV and a cracked hose under the engine cover about six months back and all good so far.

808mcv20l

if you didn't have the code before the previous repair and now you do, sounds like you bumped something or damaged something.

All those rubber hoses are notorious for cracking. Check all Vacuum hoses that run from the Airbox, Charcoal canister (inside of the left fender) to the VSV valves that then run up to the EGR valve.

If you can't find anything loose or cracked the problem could be a bad VSV valve or a clogged EGR valve or Pipe that runs down to the exhaust.

jbl-1985

All is well - codes have not come back but I have an issue with the engine now, as one exhaust valve is way out of spec, causing a very loud tick. Getting it addressed now but that's a story for another thread.